Nasal cavity
| Nasal cavity | |
|---|---|
 Head and neck | |
 Conducting passages | |
| Details | |
| Part of | Nose |
| Identifiers | |
| Latin | cavum nasi; cavitas nasi |
| MeSH | D009296 |
| TA98 | A06.1.02.001 |
| TA2 | 3165 |
| FMA | 54378 |
| Anatomical terminology | |
The nasal cavity is a large, air-filled space above and behind the
The paranasal sinuses surround and drain into the nasal cavity.
Structure
The term "nasal cavity" can refer to each of the two cavities of the nose, or to the two sides combined.
The lateral wall of each nasal cavity mainly consists of the
The roof of each nasal cavity is formed in its upper third to one half by the
The floor of the nasal cavities, which also form the roof of the mouth, is made up by the bones of the hard palate: the horizontal plate of the palatine bone posteriorly and the palatine process of the maxilla anteriorly. The most anterior part of the nasal cavity is the nasal vestibule.
The nasal cavity is divided in two by the vertical nasal septum. On the side of each nasal cavity are three horizontal outgrowths called nasal conchae (singular "concha") or turbinates. These turbinates disrupt the airflow, directing air toward the olfactory epithelium on the surface of the turbinates and the septum. The vomeronasal organ is located at the back of the septum and has a role in pheromone detection.
The nasal cavity has a nasal valve area that includes an external nasal valve and an internal nasal valve. The external nasal valve is bounded medially by the
Segments
The nasal cavity is divided into two segments: the respiratory segment and the olfactory segment.
- The respiratory segment comprises most of each nasal cavity, and is lined with ciliated pseudostratified columnar epithelium (also called respiratory epithelium). The conchae, or turbinates, are located in this region. The turbinates have a very vascularized lamina propria (erectile tissue) allowing the venous plexuses of their mucosa to engorge with blood, restricting airflow and causing air to be directed to the other side of the nose, which acts in concert by shunting blood out of its turbinates. This cycle occurs approximately every two and a half hours.
- The olfactory segment is lined with a specialized type of pseudostratified columnar epithelium, known as Bowman's glands. The axons of the bipolar neurons form the olfactory nerve (cranial nerve I) which enters the brain through the cribriform plate. Bowman's glands are serous glands in the lamina propria, whose secretions trap and dissolve odoriferous substances.
Blood supply
There is a rich blood supply to the nasal cavity. Blood supply comes from branches of both the internal and external carotid artery, including branches of the facial artery and maxillary artery. The named arteries of the nose are:
- Sphenopalatine artery and greater palatine artery, branches of the maxillary artery.
- Anterior ethmoidal artery and posterior ethmoidal artery, branches of the ophthalmic artery
- Septal branches of the superior labial artery, a branch of the facial artery, which supplies the vestibule of the nasal cavity.[8]
Nerve supply
General sensory innervation is by branches of the trigeminal nerve (V1 and V2):
- Nasociliary nerve (V1)
- Anterior ethmoidal nerve from the nasociliary nerve (V1)
- Posterior nasal branches of maxillary nerve (V2)
The nasal cavity is innervated by autonomic fibers.
Function
The two nasal cavities condition the air to be received by the other areas of the
Clinical significance
![[icon]](/File:Wiki_letter_w_cropped.svg){kind=small} | This section needs expansion. You can help by adding to it. (February 2011) |
Diseases of the nasal cavity include
- Deviated septum- a shifting of the wall that divides the nasal cavity into halves
- Nasal polyps- soft growths that develop on the lining of the nose or sinuses
- Nosebleeds
- allergies. The main symptom is a runny nose.
- Nasal fractures, also known as a broken nose
- Common cold
- Sinonasal tumors [9]
See also
References
- ISBN 978-0-7020-5230-9.
- ^ "Nasal fossa". TheFreeDictionary.com.
- ^ Knipe H. "Ostiomeatal complex". Radiology Reference Article. Radiopaedia.org.
- ISBN 978-0-323-24098-7.
The nasal vestibules are the two entry points into the nasal cavity. Each is a triangle-shaped space situated in front of the limen nasi and defined laterally by the lateral crus and alar fibrofatty tissue, medially by the medial crus of the alar cartilage and the nasal septum and the distal end of the cartilaginous septum, and columella.
- PMID 28340649.
- PMID 24427685.
- ISSN 2168-6181.
- ISBN 978-0-683-06141-3.
- PMID 31604553.
External links
